车桥系统空间非平稳随机分析

采用虚拟激励法将轨道高低、方向和左右轨高差不平顺转化为一系列简谐荷载,将非平稳振动分析转化为确定性的时间历程分析,进行三维车桥系统空间非平稳随机分析。采用分离迭代法求解车桥系统运动方程,运用三倍差原理确定系统响应的最大和最小值,讨论系统响应的功率谱密度。研究表明:车体振动、桥梁跨中横向响应和轮对受到的横向轮轨力的随机性较大,轨道不平顺是其主要影响因素,桥梁跨中垂向响应及轮对受到的垂向轮轨力主要由确定性荷载引起。

Spatial Train-bridge Coupling System Non-stationary Stochastic Responses Analysis

The pseudo-excitation method(PEM) was applied in the spatial train-bridge coupling system non-stationary stochastic responses analysis.Track vertical profile irregularity,track alignment irregularity and track height difference irregularity of left and right rails were transformed into the superposition of a series of deterministic pseudo harmonic surface unevenness and non-stationary random vibration analysis was translated into deterministic time-history analysis.Separate iteration was applied in solving the coupling system equation.The maximum and minimum system responses were obtained on the basis of the 3σ principle.PSD of the system responses were discussed.The results show as follows: Responses of the train body,lateral responses of the bridge and lateral wheel-rail forces have large randomness,and track irregularities are the primary influence factors;bridge vertical responses and vertical wheel-rail forces are caused by deterministic loads.